Improving pressure from an existing Sprinkler head

Hello All, looking for some help with some pressure issues. I was having coverage issues so I decided to move the existing sprinkler head (Sh1) which is fed by ½ inch poly flex pipe 7 feet further into the corner and then I added new sprinkler head (SH2) 15-20 feet from SH1 using a connecting tee right before SH1. The problem I am having is the pressure is not as strong as I would like. My existing system was installed with 1inch distribution pipes that steps down to 1/2 inch to feed the individual sprinkler heads. I don't have the option to find the 1 inch pipe that feeds that zone with SH1 and SH2. Any suggestions?
I was told one possible solution is that if I step up the ½ inch to ¾ inch and then only use ½ to feed the sprinkler heads then I could get a little more pressure. Does this make sense or is even plausible? Sorry for the long message.

 

Going from 1/2 to 3/4 to 1/2 will not increase pressure. You did not say what type of sprinkler head you have but if they are pop ups, there is a filter inside of it and it could be clogged up. I've seen debris (mud and stones) inside the pipe that could be blocking water flow. At these sprinklers remove the spray heads or the entire sprinkler and flush the lines. Sometimes, there could be a leak at a glued fitting or from a cracked pipe causing it to lose pressure.